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<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>01-入门案例</title>
    <style>
        div1{
            border: 1px solid red;
            width: 60%;
            height: 500px;
            margin: auto;
        }
    </style>
</head>
<body>
<h1 align="center">这是我的第一个HTML入门案例</h1>
<u>zheshiyige<br/>ubiaoqian</u>
<br/>
<hr/>bbbbbbbbbbbbb
<span>skdjfhajklsdhfkjshdf</span>
<span>skdjfhajfhskjdflajsdlkf</span>
<div1>jefkljskdfjklsjdflj</div1>
<div>fhjksdhfklasjdfkl</div>
</body>
</html>